Mini Nuclear Power Plants

[insane_alien]

I don't know, can't you just let it radiate out into the open while on land?

 

nobody likes big 20 acre radiators that make it uncomfortable warm and windy due to convection currents in their back garden.

[Sayonara]

I would have thought that is not fast enough.

[SkepticLance]

Cooling tower technology is well developed, efficient, and has the bugs ironed out. In other words, it is the smart way to go for cooling reactors.

 

Nuclear waste is a problem mainly in the political sense. There are excellent disposal systems available to us, but politically active lobby groups do not permit this to happen. Every time such a system is mooted, some bunch of activists oppose it, and our democratic governments listen to the lobbyists.

 

In the 1940's and 1950's, the standard disposal system for an awful lot of nuclear waste was to put it into steel 200 litre (40 gallon) drums and drop them into the deep ocean. It has been calculated that, at normal corrosion rates at deep ocean temperatures, there is now no steel left! All the nuclear waste has entered the deep ocean - some as sediment, and some as solution. In spite of strenuous efforts, no-one has been able to measure any environmental damage.

 

The Soviet Union used to dissolve nuclear waste in strong acids, and dilute them massively in water, and then send it via pipeline into the Arctic Ocean. To date, no-one has been able to measure any environmental damage.

 

In other words, nuclear waste can be disposed of safely. My preferred option is to place it in secure storage for up to 20 years, to permit the short half life isotopes to decay, and then dissolve it in strong acid, then heavily dilute and then dispose of in the deep ocean. This technique is permanent. You need not even think about it thereafter.

 

The total tonnage of actual radioactive isotopes produced annually world wide (concentrated waste) is less than 200 tonnes. This dispersed in the oceans will eventually reach a concentration of 1 part in 5,000,000,000,000,000. The contribution to ocean radioactivity will be way less than background. While it will initially be somewhat more concentrated, it will disperse quickly and environmental damage is likely to be zero, if the initial dilution and dispersion is done with proper care.

[CaptainPanic]

I don't know, can't you just let it radiate out into the open while on land?

You can cool with air in stead of cooling towers. But that would only be bigger. If you want to transfer a few megawatts to normal air at a max. temperature difference of 50 degrees, then you will require an enormous heat exchanger. The cooling towers are actually one of the more efficient and certainly more cost-efficient ways to do it. Dumping the waste heat into the sea / river / lake is even cheaper, which is why so many power plants are built near water. Those often don't have a cooling tower, unless there is a limitation to the heat they can dump in the surface water.

 

The total tonnage of actual radioactive isotopes produced annually world wide (concentrated waste) is less than 200 tonnes. This dispersed in the oceans will eventually reach a concentration of 1 part in 5,000,000,000,000,000. The contribution to ocean radioactivity will be way less than background. While it will initially be somewhat more concentrated, it will disperse quickly and environmental damage is likely to be zero, if the initial dilution and dispersion is done with proper care.

 

That actually makes sense. But I have never heard any nuclear engineer/scientist/journalist or whoever involved in the nuclear business propose that we just blow up (dilute in a controlled way) the nuclear waste in such a way that we evenly distribute it over the entire earth as fast as possible.

 

This idea will probably have a serious marketing problem

But since it is done in the Soviet Union, I guess the concept is known to those involved in the business.

 

In stead, every proposal is about building some enormous cave system where we can store the stuff. I don't like that idea, simply because humans have only produced a couple of (monumental) buildings that have lasted 5000 years (the pyramids). Everything else we've built is much younger and is already falling apart. Nuclear waste needs to be safely stored for much longer. I just don't believe anyone who claims it's possible to build something that lasts 100000 years.

 

I agree with SkepticLance's idea to temporarily store it for the fast decaying isotopes. Then dump it.

Or even better: no nuclear energy at all. I don't see why we'd invest in anything other than sustainable energy. But that's off topic.

Edited January 26, 2009 by CaptainPanic

[Sayonara]

I don't like that idea, simply because humans have only produced a couple of (monumental) buildings that have lasted 5000 years (the pyramids). Everything else we've built is much younger and is already falling apart.

But that's partly by design. If we set our minds on making a building that would last thousands of years, we'd be able to surpass the pyramids with relative ease.

[CaptainPanic]

But that's partly by design. If we set our minds on making a building that would last thousands of years, we'd be able to surpass the pyramids with relative ease.

Except that nobody is hurt if a pyramid has a little crack to the outside environment... but any storage for nuclear waste should be completely closed, or water will get in and start corrosion and leakages.

 

Sure we can build something that is still there after 100000 years. But I doubt we can build something that is totally closed and remains totally closed for 100000 years (at a price that we can afford, because we have affordable alternatives that produce no nuclear waste at all).

[insane_alien]

its actually really easy, we just have to look at the oklo site.

 

natural nuclear reactor, more nuclear waste than we'd produce in 100 years if we fully switched to nuclear for EVERYTHING including mobile phones and stuff no special containment, full contact with groundwater and.... safe!

 

step 1/ make cavern deep in mountain/geologically safe area

2/ line with concrete

3/ fill with waste

4/ seal it up and make it really obvious going in there would be a fatal idea. a half kilometer of concrete in the access tunnel should do.

[SkepticLance]

And for Captain Panic

The maximum time that waste has to be kept safe is 10,000 years - a factor of ten less than his figure. At the end of 10,000 years, it is still radioactive, but no more than natural granite (which contains uranium).

 

My second idea of how to deal with waste is Western and Southern Australia. There is a point about the junction of these two states that is more than 1000 kms from the nearest city, and hundreds of kms from any town. It is extremely arid, unpopulated, and geologically so stable that we can expect no earth movement for a million years or more. Simply dig a bloody great hole - perhaps 3 kms diameter, and one km deep. That will hold all the nuclear waste all the people in the world can make for the next 10,000 years. The fees to collect such waste would make Australia the richest nation on Earth. Like all such great ideas, though, this will not happen, due to the lobbying of thousands of idiots.

[insane_alien]

Simply dig a bloody great hole - perhaps 3 kms diameter, and one km deep.

 

i think you overestimate the amount of nuclear wast fissioning eveything we can would produce.

 

also, there is speculation on running fission waste around fusion reactors. not only to block the hefty amount of neutrons fusion produces but to get some useful energy out of it and transmute the waste into stable isotopes.

[Mr Skeptic]

nobody likes big 20 acre radiators that make it uncomfortable warm and windy due to convection currents in their back garden.

 

Isn't the proper cooling system for a nuclear power plant, to sell the steam to the nearby people, who can use it to heat their water or their house? I call it the "using the city as a heat exchanger" system